Because so long as someone keeps writing checks, that's what the system can provide them.
Good news for you, Jerome: no one writes checks anymore, for anything!
or trust someone without a single logged dive to "Rescue" you
But seriously... your definition of "logged dive" seems to require that only a dive that someone does on their own, without an instructor, can provide any worthwhile experience. You seem to think that just because an instructor is with a diver and the dive is done as part of a course, it can't provide any useful experience. But most agencies, as far as I know, want divers to log all of their dives, whether within the context of a class or not. Your definition of "logged dive" is different than the generally accepted industry definition.
If you got a basic certification and have done a lot of diving and it's worked for you, great. But it's very short-sighted of you to think that your way is the only reasonable way or that your way would be the best option for everyone. In fact, just the opposite is true: a lot of different people need a lot of different options to accomplish the same goal.
As for your question about who I would trust to rescue me... let me modify the scenario slightly: would I rather have someone that has had basic training and 1000 dives on their own, or a newly minted DM that has only 80 dives be in the position to rescue me? Hands down, I would take the newly minted DM for several reasons: they just had the relevant training, they made the decision to become a DM (which says a lot about their interest in performing the duties that come with), and at 80 dives they have as much diving skill as would be necessary to rescue me as someone with 1000 dives would (Note: I'm not arguing that someone with 80 dives has the same level of skills, in general, as someone with 1000 dives; I'm arguing that the level of skill necessary to assist me would not significantly improve between dive 80 and dive 1000.)
The fact is that someone who just has 1000 dives but no rescue training is really really good at basic diving skills. But that doesn't make them a competent rescuer of other divers. It's like the difference between someone that can sink 100 free throws in a row, versus someone who can actually play basketball.
And last... I'm sorry that you're angry about the availability of training beyond the basic course for divers that decide such training could be worthwhile. Some people probably agree with you that no such training should be available, but there are others that think the current system, while perhaps not perfect, does provide an overall benefit to the scuba industry.